Wipers 71
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
There is a wiper solenoid that is mounted behind the tach. This solenoid, looks a lot like the TCS solenoid, but I'm not sure if it's the same.
The electric wiper motor will not function unless the wiper door is open. You can see the contact by the wiper motor.
My guess is either your solenoid is bad, or one of the vacuum, or the electrical connection was knocked loose.
The electric wiper motor will not function unless the wiper door is open. You can see the contact by the wiper motor.
My guess is either your solenoid is bad, or one of the vacuum, or the electrical connection was knocked loose.
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
Burning Brakes
Joined: Feb 2011
Posts: 850
Likes: 12
From: Shakopee MN
Roger, do you know how to test this solenoid? I've been looking at mine and trying to understand it's purpose.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
testing- vacuum should flow from the metal nipple to the 90 degree down plastic nipple,after you apply 12v and a ground to the 2 electrical spades the flow should stop.
The straight plastic nipple (usually has a block of foam on it)must remain open to bleed off vacuum.
I think Willcox has a good pic and description,I'll see if I can find a link.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Here it is. http://willcoxcorvette.com/instructi...function_2.pdf
Willcox has a bunch of help articles on his site.
Go to the Willcox site
Type wipers in the search bar
Click search
Down at the bottom will be Repair and Install Help
Click on "Corvette Headlamp and Windshield Wiper Vacuum Small Parts, How They Operate!"
Then click on Supporting Documentation
Then scroll down to the Tach Solenoid
Lots and lots of good reading in the Repair and Install section
Willcox has a bunch of help articles on his site.
Go to the Willcox site
Type wipers in the search bar
Click search
Down at the bottom will be Repair and Install Help
Click on "Corvette Headlamp and Windshield Wiper Vacuum Small Parts, How They Operate!"
Then click on Supporting Documentation
Then scroll down to the Tach Solenoid
Lots and lots of good reading in the Repair and Install section
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
The wiper vacuum system work the same as the headlight system.
These systems have vacuum actuators, and relays. The relays work like electrical (SPST) relays. The vacuum lines that run thru the dash are part of the control line (white stripe) to the relay.
Both the headlights, and the wiper door are designed to fail open, and the relays are designed to place the actuators in the down position when the control line has vacuum. So, the headlight switch, the wiper solenoid, and both the overrides are designed to stop vacuum along the control line when the actuator is supposed to go to the up position.
This is what Roger meant by the solenoid needing to 'dump the vacuum'. You should be able to test the solenoid by applying 12v and see that the airflow thru the solenoid is pulled from the rear, open air/filtered port. Without 12v the rear port should be closed, and air (or vacuum) would flow thru the other 2 ports.
*edit* - Roger beat me too it.
These systems have vacuum actuators, and relays. The relays work like electrical (SPST) relays. The vacuum lines that run thru the dash are part of the control line (white stripe) to the relay.
Both the headlights, and the wiper door are designed to fail open, and the relays are designed to place the actuators in the down position when the control line has vacuum. So, the headlight switch, the wiper solenoid, and both the overrides are designed to stop vacuum along the control line when the actuator is supposed to go to the up position.
This is what Roger meant by the solenoid needing to 'dump the vacuum'. You should be able to test the solenoid by applying 12v and see that the airflow thru the solenoid is pulled from the rear, open air/filtered port. Without 12v the rear port should be closed, and air (or vacuum) would flow thru the other 2 ports.
*edit* - Roger beat me too it.
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